Marina Poje Sovilj

Assessing the radiological load on the environment in the middle Danube river basin on the basis of a study of the Kopački Rit Nature Park, Croatia

A study of the environmental radioactivity in the Kopački Rit Nature Park, Croatia, is presented. This wildlife reserve is part of the Middle Danube River Basin, and it is exposed to various pollutants due to a number of human activities in the surroundings, where there is a nuclear power plant and also urban centres and areas of intense agricultural production. Results for the activity concentrations of soil and surface water samples do not indicate any elevated radioactivity level, which is confirmed by on-site measurements of ambient dose rate equivalent. An assessment of the radiological load on the local biota, carried out using the ERICA tool, implies an overall low radiological risk even if conservative values of the risk quotient are used. Therefore, human activities do not have a significant effect on the radiological load on the Kopački Rit area. A similar conclusion might be made with regard to numerous similar environments in the Middle Danube River Basin.

Natural Radiation Dose and Geomagnetic Effect

Earth keeps getting bombarded by high-energy particles that originate in the outer space and in Sun. Cosmic radiation in Earth’s atmosphere consists of a photon and directly ionizing component and a neutron component. Charged particles of cosmic radiation are deflected by the geomagnetic field that is more expressed at the equator than near the poles. Photon radiation was measured by Radiameter ESM FH 40G-L10 at 26 main meteorological stations in all parts of Croatia. The correlation between the photon dose rate and latitude was examined, as well as multiple correlations for the photon dose, latitude and altitude. The obtained positive correlation coefficients were statistically significant. The neutron component of the cosmic radiation was measured by series of nuclear track-etched detectors, at the same meteorological stations during one year period. The dependence of the neutron dose rate on the altitude was found and the associated equation of the linear regression was derived. Relation between the values of neutron dose N and altitude h, showed significant dependence of the neutron dose on altitude. However, the correlation of neutron dose and geographic (geomagnetic) latitude was not statistically significant, probably due to a small range of geographic latitudes for the measuring stations in Croatia.

Current radiological situation in Slavonski Brod, Croatia: is there a reason for concern?

Abstract For years, the town of Slavonski Brod in Croatia has been facing serious problems with air pollution, which is usually attributed to an oil refinery across the Sava River in Bosnia and Herzegovina. While the air quality is being monitored rigorously with regard to nonradioactive matter, no attention has been paid to the possibility of a coincidental radioactive pollution. This study is the first to have addressed this issue. We measured ambient dose rate equivalents at 150 sites and found that none exceeded 120 nSv h-1, while the average was 80 nSv h-1. Gamma-ray spectrometry of the collected river water and soil samples did not reveal any unusual radioactivity either. In other words, we have found no evidence of radioactive pollution that would endanger the health of the residents of Slavonski Brod.